If I was doing a conversion and wanted maximum replability and parts commonality for the lowest price I would:
1. Buy an (accident damaged) NPR truck for the engine and gearbox (etc.) - preferably 4BD1T - but 4BD1 would also be fine.
2. Buy TheGrubb's isuzu GB to LT230 adaptor.
3. You will also need to sell your LT230 and swap it for a disco 1.2 or a 1.003
An alternative to 2 would be to convert the LT230 to a divorced setup, but this would mean that the propshaft may be a bit short on a 110. On a 130 it would mean you can use a 110 prop.
Some of the landie (aka non-isuzu) parts on a 110 (clutch plate, speedo cable etc...) are the same as a V8 110, some are unique. Most of these parts rarely need replacing, but having a truck clutch and truck box from the start will mean you can scavenge bits from just about any NPR / GMC4000 etc... on your travels.

