edit: TRB hadnt posted yet when i started this, i apologize for any redundance. guess it took me a while to type and make sense of my ramblings.
...........................
i share the sentiments that slick 88 does, though not nearly as passionately.
get lock actuators from
www.partsexpress.com
i got mine for 3.37 each on sale.
it sounds like 88 did his differently than mine. i followed jrichker's write up:
http://jrichker.stangnet.com/Mustang_tech/door_actuator_fix/1_of_8_door_actuator.htm
NCD, i hope that kinda answered some questions too.
i chose not to purchase the stuff he did. as usual for Joe, his retrofit will long outlast the car. i cut corners. things you can change and still have functionality: instead of drilling the door, you can simply get some nails that are the same gauge as the new lock acuator holes. take two, cut them each so that they are each half the distance from bushing to bushing, and slide them in through the bushing on each side. they met in the middle (same structural elements as one bolt). put tape on each head so that they cant back out. the nails cant back out anyways. i recommend this if you have plastic brackets, as they are not in the same place as the metal ones jrichker had. so his measurements will be off. this is easier anyways.
you can use muffler strap to bridge the distance from the actuator rod to the linkage where the stock actuator hooks up. get some at parts store, cut a piece that has two holes (two holes long). cut on the outer edges of the adjacent holes, so you have more metal to work with. i rounded the edges with tin snips and wrapped both ends with a few passes of electrical tape. then cut through the tape to expost the hoes again. idea being, that the metal is now wrapped in tape and less likelyto chafe anything. use a small machine screw and lock nut to attach the actuator rod (it has a hole on the end of it) to the metal bracket you just made. i used a zip tie to attach the other end of the metal bracket to the linkage where the stock actuator attached (there is a hole to attach through).
this worked perfectly for me. my point to all this is, unless you have the stuff jrichker used on hand, my way costs even less (i had it all on hand except for lock nut to attach the actuator rod to the metal bracket. cost pennies at the home store.
like i said, his way is better, but mine works for cheap. it is really satisfying to know that i can replace actuators for under 4 bucks (i order from parts express several times a year (restock
so shipping cost is not an issue. buy 3 or 4 the first time and you are good forever.
it takes anywhere from an hour to several (i spent several re-engineering stuff). i did scrap the nails and use a bolt as warbird did, only because i want to measure and provide him with exact measurements for the plastic brackets. i did not get it exact, so i didnt give info to him. i can measure if you want, but the hole is outside the door panel, so its ugly. i recommend the nails. they wont come out (friction hold them in, they dont have lateral room to back out regardless). and the second one you do (i.e., other door) will take 1/10th the time since you know how to do it.
if nothing else, this write up shows you how to do it (it sounds like more of a PITA than it really is). i ended up lookin at his finished actuator with the linkage (on the last page IIRC) and re-did it with stuff i had.
if you wanna do it, and have questions, post or pm. im sure myself or 88 can help out. definately worth it to me (just in principle; im not paying 40 bucks for actuators that break all the time). i share 88' sentiments, but dont articulate so, as everyone has different levels of skill. (i would not have done it when i was startin out wrenchin on cars, as i didnt have the skill. ok, i would have, but im trying to make a point). different priorities for different people (if i was rich i wouldnt care. LOL).
good luck with whatever route you take.
Anyway, I came off as a jerk in my post and I'm sorry again, I was having an extremely bad day and was not in a good mood 
Sorry ndc5.0lx, but I have no idea about those bushings, I've never screwed with them before. Let me know when you figure something out, good luck!
