This from Ron Beckett in Australia:

Seen on the Castlemain Rod Shop (http://www.rodshop.com.au/) web site (Australia):

Adaptors:

AP 27 Range Rover to 253-308 HoldenÊ
AP 28 Range Rover to Chev V8
AP 53a GM Turbo & Powerglide to P76 Leyland V8Ê
AP 53b GM Turbo & Powerglide to Rover V8Ê
AP 79 Range Rover T/Flite Auto to Chev V6 & V8Ê
AP 82 Range Rover ZF Auto to Chev V6 and V8Ê
Ê
Bellhousings:

BH 55 Landrover 4 cyl. to Holden 6Ê
BH 56 Landrover 6 cyl. to Holden 6

You could also look at the Mark's site http//www.marks4wd.com
There some Rover options here http://www.marks4wd.com/rangeroverindex.html and they have US dealers listed here http://www.marks4wd.com/osdist.html
+++++

I want an adapter from a 2.25 to an SM420, and from a 200Tdi to a Toyota R151 :(