Yes it can be done. You do not have to do any cutting of the fenderwells, and yes you can fit a 351 in without much more trouble too. Here's a list of things that i can think of that you will need:
1:302/351 Motor
2:Clutch & tranny combo
3:New motor mounts(convertible type) and tranny mounts(suggested)
4
ual hump crossmember(for dual exhaust)
5:8.8 inch rear end(you'll break the original in no time)
6:Wiring: pretty straightforward, just mark where they were before & use what you need.
7:Suspension:you'll probably want to change the front springs unless it's gonna be a dragger, rear springs suggested, new shocks/struts suggested.
8:brakes: 87-93 stangs came with bigger front discs, you'll want to change to those for acceptable braking.
Thats a pretty basic list, you'd be best off buying a 87 and up parts car w/ good drivetrain and convery it to carb. A 351 would not be that much more expensive when starting from a 4cyl, but you would have to get headers, accessory brackets, etc to get it all running together. Ask away any questions..
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mark brooks. '85 gt hatch,ssm bars,draglites,msd ignition,dual quad setup,8.8 rear3.73,electric fuel pump,supertrapp exhaust,motorsport trans,many many more...
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