This comes up every now and then-you can do a search or Ram starters and find old info. A short recap: You CAN NOT use the new Ram "X" style bendix ( or jet joe bendix) on the older Ram compressor nuts. Ram had two types of starters/bendix/compressor nut combos. The original ( and indeed most of the RAMs out there not converted) had a mostly flat faced compressor nut that was slightly convex. Most have hash marks ground into the face of the nut. It may or maynot be magnetic for a Hall sensor. The bendix had an O ring that sat proud on the face of the nut and pressed against the ridges. The 750/1000 had a coreless BB starter. It was made by Fulhauber and the motor alone cost $125.00 IMO this starter and the early autostart software is what killed RAM. The motor was not up to the job, the O ring bendix was prone to slipping on the higher mass 750/1000s (worked OK on the 500s) this resulted in low RPM on startup and a ton of flame.
Towards the end they went to the "X" style starter. This style is what is used by everybody else now. It has a recessed O ring that slips over the new "Acorn" shaped compressor nut and grabs it around its circumfernce. Better grab, no slipping. You will notice the bendix is larger and longer.
If you try and use a X style bendix on a flat comp nut all that will touch will be the outside of the brass bendix on the aluminum nut-no workee.
Yes the turbine will need to be rebalanced if you change the compressor nut.
Carlos can convert it over but it is pricy as not only does it need balancing but the compressor case needs to me machined to fit the new starter.
You can use a WREN wand starter to start a flat faced nut Ram-I did it for a while to get rid of the bottle. Scott