Paul,
A while ago I produced a pdf of the gearing set ups for non gearbox Myford lathes, which will do equally well for your Zyto lathe. The tables cover Imperial, metric, BA, DP and Mod pitches, plus some obscure pitches so there is a lot of information for your money
If you would like a copy, it is for sale at £2.50 in support of the Remap charity, any funds it generates go to them Please use my Paypal Identifier wood_y(at)btinternet(dot)com quoting 'Remap Gears' and a copy will be sent to the e-mail address you use in the transaction
Note there is an underscore between the d and the y
Regards
Brian