Fact checker - ?
The referenced number J-6230-1 are dynofocal mounts, not conical. Not sure why they are even relevant to this thread.
Check this thread - and photos -
http://www.vansairforce.com/community/showthread.php?t=53007
J-6230-1 is a KIT, a collection of parts;
J-6113-1, Vibration Isolator (the vulcanized cone, kit has 2 for each mount) These have 'orientation holes' which apparently may be useful for turning and knowing the orientation of the eccentric spacer.
Y-8745-S, Spacer (an eccentric cylinder/spacer, kit has 1) Can be used to 'clock' the four corners of the engine mounts.
I tried to buy a J-6113-1 cone separately (to replaced a lost item), but only Lord as a source, and even there couldn't get it.
(for RV-6/7/8/9A) The AN970-8 washer, and the AN8-45 bolt with matching nut AN310-8, can be acquired separately. [Different for RV-3/4].
The Installation sheet for the Conical Vibration Isolator shows a comparison between the two 'styles' - and the OVERALL length of the J-6230-1 kit is (2 5/32") compared to the 'conventional' old rubber cones (1 27/32").
The NEW style is 3x the cost of the ORIGINAL (conventional) but they are significantly different mechanically.
There is a relationship to the A/C that used this KIT ... but don't remember at the moment (Luscombe?). It should be obvious, but whichever is chosen, the four mounts should be the same versions (consistency).
Not yet flying ... soon, but went with the NEW ones.