New project new problems

Evening all, I have a 1972 Series 3 88" thats a running restoration project. I have this weekend found a couple of confusing issues that I would like your comments or advice on....
I went to replace the barke shoes, cylinders and drums to find that although its an swb there are two adjusters on teh anchor plate at the back. Once the drum was off it confirmed the cylinders were different and the parts I had bougth were no good. Is this common, why would someone have put lwb wheels on and swb landy.
Also my cab appears too long for the cab area. Its a pick up style and there is a gap behind the seats. I can see fixing holes behind the seats should these all marry up for definite.

Any advice would be grateful

Thanks

because the twin cylinders are more effective as brakes and after 1980ish where fitted to all models not just 109,there should be a plate that truck cab fits to between rear bulkhead and cab

Thanks James bit of a relief really. Any ideas where I can get one of these plates for the rear b/head as it didnt come with one.
Cheers jason

ebay, or findapart or breakeryard on internet etc

As James says it's very common to find LWB/later 11" drums on 88s simply because they give a very worthwhile improvement to the brakes. Smile and be happy, you have an upgrade for free.