Reversed Battery Polarity…Now the car won’t start

Alright...so I got my son to help me with my car. 95 Mustang GT Vert 5.0. We put in a new 255 LPH in-tank fuel pump so that I wouldn't have to worry about future upgrades outpacing the pump, running LiveWires, MSD pro-billet distrubutor, MSD 6A box, DUI TFI and Coil. BBK SS11 intake, 75mm fox body throttle body conversion, C and L 76mm MAF calibrated for 19#, and stock 19# injectors, double roller timing chain, stock heads, BBK long tube headers and x pipe with cats, MAC cat-back, fidanza aluminum flywheel, and Spec stage 3 clutch. We also put in a new battery and after my son hooked up the battery leads he reversed the polarity. Now it won't crank. I can hear the pump prime when I turn the ignition switch, and I have only seen one 10amp fuse that I have had to replace #18 I believe for the EEC power relay coil. None under the hood. I haven't checked the the relays or the metal fuses in either the interior or engine bay (I mean the non-plastic, see-through, colored fuses) I haven't checked the MSD box yet either...I could by-pass it and reconnect the coil directly again to check, but The car turns over, but will not crank and run. If anyone else has ideas about what is wrong, things to check, or anything at all I would love to have your input. One additional question...with the fuel pump that I put in and plans to eventually change the heads...what the biggest size injectors that you would use that the 95 computer would tolerate right now, but would be usefull with bigger heads. Fuel pressure adjustment amount suggestions? Thanks!

Any location other than the engine bay or inside driver? I haven't run a continuity check on the metal fuses...just the plastic colored ones that I see through and have checked. I replaced the only one so-far that I could find burned out.

Well the changes were already made...I just had an issue after I changed the fuel pump. I did figure out what happened. My MSD 6A shorted along with with the screaming demon coil. It work after bypassing the CD box and putting in my old stock coil. I was planning to upgrade the box anyway to the new MSD Digital Programmable 6AL-2 anyway, but I wasn't planning on a new coil as it was new already...thanks for the post and potential help. I would still like some info on fuel pressure setting and max injectors though. Thanks!

Thanks for the info. I was thinking that was about as high as you could go with the 95 computer wihtout a tune. I will look for the injectors and a new sample tube for my MAF.