al pushpak wrote:No worries

I think I may have the early type cluster & I definitely have the later stronger 3rd gear, just can't find any dimensions or measurements anywhere regarding the cluster

thanks again

To my knowledge, there is no difference in the cluster third gear teeth size of early & late Pacemaker 'boxes, but I stand to be corrected.
When they fail, as the early third loose gears tend to, it will only be the teeth of that individual gear that will strip, in my own experience. If proof were needed, I have utilised a Pacemaker ' box in race & road tuned engines for years that has the centre bored cluster as my belief is that enables the best OEM type clutch components to be fitted with the centre spindle, rather than the later type which can tip @ an angle, making component clearance variable.
All Lambretta gearboxes are based upon a modular design but are 'bastard' gears to achieve the desired ratios.
Therefore, what Innocenti did to strengthen the fragile loose third gear, was to marginally increase the thickness of the teeth to gain strength by modifying the actual PCD of the gear. Taffspeed took this principle to to the extreme by producing their close ratio gearboxes which meshed special (even more bastard) cluster gears with standard OEM loose gears to produce a very strong product. Despite what you may read elsewhere (from somebody that may claim to have invented the wheel.....) they did work very well, as I believe I bought the last two sets from Ian, & they proved bullet proof.....