Outer Limits 4x4 Board

Hi ppl, have a question, hoping someone can help. Own an 83 LN46 Hilux 4x4 Dual cab, an oldy but a goody. one problem is since it has been converted from 22r to Holden 6cyl 202 Red, is the gear ratio, nothing wrong with the box, just needs a 5 speed box, had a few quotes and always in the $3000 to $4000 area, more than the bus is worth, is it possible to change the box over easily without costing so much?, on a carers pension so money is an issue, would like to change it to a Power steering, but they want $1,500 or more, so will forego PS. If it's not too costly, what box is the best?, read Supra is one way, needing an adapter, need a list of what I will need and where to get them?, if affordable got a friend who will help change it over, also will it help with fuel consumption? not revving as much in lower gear. Have restored most of it to a good vehicle, no rust, new paint, dual fuel.
Any advice will be appreciated
In West Australia
Cheers
Waz

check out www.marks4wd.com for adapters. They do quite a few adapters for different engine and gearbox combos.

Many thanks, will send an email to Marks.
Cheers
Waz