I have seen the product, "Yamabond"seemingly duplicated by a couple of different companies.
Wurth, a german based industrial supply co. has a sealer spooge similar to y-bond,it's pricey too. Permatex has one too, Item #29132, " Motoseal, ultimate gasket maker, GREY ", not too pricey & found in auto parts stores. All 3 spooges are good & look, apply & do the same thing. A good friend of mine that owns a wholesale transmission rebuilding co, says the original concoction for the spooge was german developed & licensed or copied by the other companies, the only difference is the retail price.
As Bob has advised, freezing the crank/ trans side of the cases, & warming the other side that you are assembling is necessary due to the exact diametrical measurement of the crankshaft fit in the main bearing, when both are at the same temperature.
Aprox 125 to 150 degree f will do ok. Apply the sealer to the cold parts after drying any ice or condensation from the gasket surfaces. Be sure that all the internals are lined up properly & spin tested as you tap them together with a dead blow mallet or a rubber or leather mallet. I would advise against using a press, if something is not right, you may bend or break parts. Do not be concerned with any disassembly issues of one sealer over an other, the objective is to result with it all sealed & assembled perfectly. Gaskets are cheap in comparison to your time & effort.
Good Luck! :ride: :cool: