The NAMC’s “Catalog of all Series Matchbox Models” (second edition) states that the two listed variations (i.e. KBPW and BPW) both come in either light or dark metallic green (making four variations in total).
The AIM's “1-75 Series Regular Wheels” catalogue (second printing, 1983) only has the KBPW, no wheel recess variation (36-2a) in dark metallic green.
Stannard has no variations not already listed by Nick, but Houghton splits Nick's variation code 1 (9 x 24 BPW, no recess) into two separate codes: 36b-1 is dark metallic green whereas 36b-2 is light metallic green
Leake ("Concise Catalogue of 75 Series Matchbox Toys by Lesney" (4th edition, reprinted 2006)) notes that shades exist.
U.K. Matchbox did not examine the model in any depth, but did make the following comment in Vol. 6 no. 6 (Feb. '83) p207 "...finished in an overall polychromatic metallic pale green - of which a darker and rarer shade exists...".
Could we please have confirmation of the existence of the dark metallic green variant together with details of the wheel type and presence/absence of the wheel recess.
36b Lambretta Scooter & Sidecar
Re: 36b Lambretta Scooter & Sidecar
Hello Hugh, here are my three colours of the 36b.

The Darker Green has 10x24 tread wheels and no cut-out on the side car wheel.
The Mid Green has 10x45 tread wheels and has the cut out on the side car wheel.
The very Pale Green has 10x24 tread wheels an no cut out on the side car wheel.

The bases showing the no cut out and the cut out on the side car.
George T.

The Darker Green has 10x24 tread wheels and no cut-out on the side car wheel.
The Mid Green has 10x45 tread wheels and has the cut out on the side car wheel.
The very Pale Green has 10x24 tread wheels an no cut out on the side car wheel.

The bases showing the no cut out and the cut out on the side car.
George T.
Re: 36b Lambretta Scooter & Sidecar
Thank you, George.
The implication is that Geoffrey Leake was spot on (not for the first time) when he listed the model as having shades.
The implication is that Geoffrey Leake was spot on (not for the first time) when he listed the model as having shades.