Engine stand for 312

Hi Folks
As a holiday treat to myself I removed the 312 Y block engine in my '57 Retractable on Christmas Eve with a view to fitting new rear crank seal and a few other minor jobs.
Although I have the normal type of stand which picks up on the tapped holes in the rear face of the block which mates to the bellhousing, it only uses 4 fixings: the 2 lower fixings could go into a meaty part of the block near the crankshaft centre-line. Looking at a couple of the higher tapped holes in the block however (to make up the 4) these are much less re-assuring, bearing in mind the substantial weight of this engine, and are unsupported 'stand-out' bosses in the casting, only perhaps half an inch thick. These relatively thin sections make me very nervous about mounting my engine this way and make me wonder if it is common practice amongst Y-block experts not to risk this approach but to find a double sided rotating engine stand which uses the engine mounting features found on each side of the block. Any advice would be welcome.
In addition, a good local engine machine shop advised me not to slavishly fit the grapited-rope rear crank seals again but to use a more moderen approach. They recommended I use a Dodge 318 ('75-'76) 2 piece nitrile rubber seal Part No. BS-40245. I notice MAC are offering something which sounds similar but costs c.$50! Any advice here would also be most welcome too. Dripping engines in this tidy and proud community where I live are simply just NOT acceptable, it seems!
Many thanks in anticipation.
JK

The Dodge 318 seal will work but has to be trimmed and modified very carefully. Best Gasket Co. makes a modern neoprene seal for 312 y-blocks. Remember, 292 and 312 seals defferent.

Thanks for the advice wagonman56,
I now have a Dodge 318 seal pair which are radically different with 'side ears' which I guess have to be trimmed off. Delving deeper into my full 312gasket kit, I now belatedly find a pair of 'neoprene' seals (as well as a pair of the infamous graphited rope seals). Does that mean some '57 blocks only take the rope seal and some only take the 'neoprene' seal, or are the different options provided simply to satisfy the re-build engineer's personal choice? Any help here would be welcome!
JK

I have used both neopreme and rope seals in both y-blocks and fe big blocks. I personally have no preference. The rope seal when installed properly has always done the job. I have seen more problems with the side seals not sealing properly. These must be driven all the way in or there will be a slow, but continuous, leak between the rear main cap and the block. Often times i have seen the rope seal blamed for a bad or improperly installed side seal. Hope this helps.
Bill