The AOD will sit on the stock '54 trans cross member using the ANCHOR 2253 mount. Note: It may have to be lowered an inch in order to clear the trans tunnel.
You also need a front sump oil pan to clear the crossmember. Most SB V8 Mustangs from the 60's and early 70's had front sump pans. So an oil pan for a 1968 Mustang 302 will work nicely. Spectre pans have a nice oil baffle in it. To complete the conversion you'll have to get a matching front sump oil pickup/screen.
Changing to a front sump oil pan creates an issue with the stock oil dipstick on a late model 302. You will need a timing cover that has provisions for an oil dipstick that goes down into the front sump. Again, the 1968 Mustang 302 Dorman cover (part # 635-107) with the gasket and front seal will do. These are available just about anywhere including eBay.
There are a variety of solutions here. There is a whole bag of worms here. First - early SBF(pre-69) cranks are 3-bolt. The later(post Mid-69) are 4-bolts. Then you have early V-belt drives(pre-90) and later flat serpentine belt drives. Then you have to decide how many sheaves (grooves for belts) you need. You can have as many as 4 on some v-belt applications. serpentine's may have 2 but usually just 1.
Front grease seals part number 472319 fit the hub and spindle. Hope this helps anyone with this same problem
You can mount a 55 gas tank in a 54 with very little effort or mods HAMB