heres my engine numbers and I dont tink she's a se as its not a w73
front right........XA
back passenger......506557
front bottom right...... 27n******
drivers side side ........400J
close to the dist........2
I assume these numbers are from the original engine that you have stored, right?
XA would be a valid engine code (180Hp 400) for a '77.
A '77 W72 400 (200Hp) would be WA (manual trans)or Y6 (auto trans).
If you want to verify that the stored engine is in fact the original 400, there is a partial VIN stamping on the front of the block that would match the car's VIN.