Drivetrain 1985 Convertable - 373 gearing conversion

From what I've been able to figure out is that this car has a 7.5" rear end and by looking at it's shape being more round than oval, I believe confirms that. A friend of mine has the 373 gears but they are on an 8.8" Detroit Locker. He thinks that the gears will still fit in a 7.5" rear end. Does anyone have any insite on this situation.

Or if they wont fit, does anyone have the 7.5" gears and want to trade for the 8.8"?

I've been researching this weekend and haven't found and answer to whether or not these gears will fit, but that's interesting, this one has 10 bolts.

What I have found out though is most people swap the whole rear end for the 8.8" to handle all the HP there adding. But I'm not trying to go crazy with this car, but as is, the power is pretty disappointing for "5.0". It sounds to me like the 373 gearing's going to help a lot, but I think I can get this from the stock 185Hp to something over 300hp, with some fairly simple bolt on's. Now I know I'm not the first one to say this, but I think thats all I really need, lol........

So, the 7.5" shouldn't have any problem handling the 300-350Hp. But the 2 of the 3 reasons that everyone goes up to the 8.8" are options I think I'd like to have.
1. The 5 lug wheel upgrade would be nice, then after talking to my buddy that just got new rims for his 2017 said I could have his stock wheels. I'm just a little worried that the 17" rim will be to tight up front.
2. Converting to disk breaks is a huge plus.....or is it? 70% of breaking is up front anyways. I'd like to hear opinions on this one.

Good news is, I dropped it off at a shop and had a complete diagnostics done and the only issues were a small coolant leak from the heater core line.(it's at the T were the last guy bypassed the heater core). And they couldn't nail down my idle issue, but suggested replacing the fuel filter, flushing the line, and cleaning the 2 injectors. Oh and the A/C chock does not engage, but I'm pretty sure that's because it was also disconnected for the last 6 years, I bet thats an easy fix.

Thanks mike, you've confirmed the two main things that I've been figuring out. And 8.8 gears in a 7.5 was a pretty obvious no, but I've seen stranger things. And that's my plan, get an 8.8 from a salvage yard, since I have all brand new guts, and take my time with it on a bench.

Any advice on what year make and models fords will have an 8.8 rear that's the same width? Chopping something down to size and re welding it just sounds like a terrible idea. I'm in no hurry and wanna get it done right.

The right offset 17's fit fine (I have no idea if the wheels off a new car fit right)

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From what I've found, it sounds like it'll have to be a pretty low profile tire, but they should fit. But you've made me wonder, if there's a slightly narrower rear end out there, would that help with tire fitment?

I can see that, 2000xp8. So get the shell and everything cleaned up and repainted on the bench, but add the axles and gears after it's installed.

Thanks guys, looks like I'll be doing the Central Texas junkyard crawl this weekend.