Twin wheel axle on mk2 transit

[rwd2ltrfiesta]

Not long ago bort the misses a motor home it has a single wheel axle on at mo looks unstable but bin this way for years but I'd rather the extra wheel to a, fill the insanely eempty space b, stability
the axle I have is from a 54 plate minibus am I right in thinking it's not a simple bolt on mod the leaf springs don't look like they fit,

suggestions

[mexicotait]

Loads of info on the mk1 mk2 transit forum about doing this
Think prop is different and a few other things but it's been done loads so can't be too much hassle