The 370 does not ring a bell. The 361 and 391 were both FT (Ford truck) series engines. They both had the same cyl bore of 4.05 but the 361 a 3.50 crank stroke like the 352 and the 391 a 3.79 just a hair more than the 390 and 427. Both engines had forged steel cranks. As far as casting and Ford part numbers there are lots of online and available reading material that fully covers these. Also a master parts catalog available on CD. A very good book to have is the Steve Christ "How to rebuild big block Ford engines" This book covers rebuilding, part ID, different FE engines in general and has a section of the more common blocks, heads, cranks , rods etc...with numbers, years and application. Also block bore sizes, crank sizes, valve sizes, it goes on.... In the mean time I'll look for a few sites. Here is one www.woodyg.com scroll down to the FE big block section. You can take it from there.
G.