I dunno what a '89 go body is, but all 302/5.0/351W & C have same bellhousing bolt pattern. NOTE Balance of early & late 302/5.0 engines is different. Install a late engine with a early flywheel(or the reverse) and you'll have a dandy paint shaker.
Late model bellhousing are deeper than early models. You will need the longer input transmission to go with it if you talking manual transmission. Don't know nothing about automatic transmissions
Well, if you are going to use a T5, then you would be good to go! Then you would need correct flywheel and all related parts for conversion. Do you currently have a manual tranny behind your 302? David
should work well, if it doesnt have a matching bellhousing then make sure you get the right one. the ones off the SN95 (late models) mustang are longer to accomodate a longer input shaft. as far as clutch mechanism... Im in the middle of the swap right now and am going hydraulic.
Don't know if you know this or not, but make sure the firewall's well reinforced where the master cylinder's mounted to keep it from flexing, especially important if you're going to drive it a lot.
Or, if you have an old bellhousing, you could just use a California Pony Cars adaptor to mate the T5 to the old bell and use the existing clutch linkage. https://www.cjponyparts.com/cpc-t-5-adapter-plate-for-6-bolt-bellhousings-1965-1973/p/T5AP/