hi everyone could anyone tell me if the mesurements for the wishbones in the book are right before i start making them and if not could someone sort me out with the right ones please

The top bone is the "wrong" one. It doesn't give enough castor. You need to offset the top upright mounting by more. It's been covered recently I think, so a quick search should reveal the details which I can't remember. Although an offset of 22mm rings a bell.

thanks for your reply i did have a quick look before posting question but ill have to have a better look! would anyone know where i could get plans if i was to use sierra uprights cos the bones have to be made different dont they ?

Better to buy wishbones in rather than make them they are such a fiddle to make they least enjoyable job in the whole build.

If however do you decide to make them be aware apart from the caster issue the book jig design is inadequate and the book lower wishbone design is deeply flawed.

This subject has been discussed many many times if you do a search you should find pictures of improved wishbone designs as supplied by the most respected names in the Locost parts world.

ok thanks im quite new to this so ill try to have a look thanks again and i dont know much about wishbones

May well be best to buy some then. As said, getting them right can be a PITA. They aren't overly expensive so if you're not sure, why trust your life to some you've made? I reckon I could make a set, but as for getting them accurate and equal? That may well be another thing.

Be careful which ones you buy (if you feel you have to), as some are awful in design and manufacture. 22mm is the correct setback for 5°30' (which I used, but this can be considered an absolute minimum) on Cortina knuckles.
Rescued attachment Wisbone Modification.JPG

the easiest way is to make the wishbones to the book dimension but lean the front assembly back by an extra inch and adjust the fu tubes to fit in.

ok thanks for the pic and thanks everyone for your help