[gazhillAE]

Regarding the wheels situation, Schumacher sell preglued cougar SV wheels in slim and normal width they should both fit your b4.1 mate.

Tyre wise you've got the following as a guide from memory im right with all these I'm half asleep like:-

Silver-softest-Rarely used again, softer than yellows, wear quicker, work well on sandy tracks I think
Yellow-mostly used on astro and grass and any other surface, most popular. You also have stagger rib for 2wd front!
Blue-work well on grass, worth trying them back to back with yellows, rarely used now
Green-hardest-work well on grass especially wet and muddy, hard wearing also

Can't remember if blue goes before green or the other way round for certain but blues are very rarely used if not at all!

Gaz