I have read the LOng thread on this subject but have not come up with an answer, is 19mmx 1.6 wall tube OK for the wishbone arms?

Is that for the top or bottom bones?

The consensus seems to be go a bit heavier on the bottom, although it depends a lot on where your shock will mount.
I went 25mm x 2mm (ERW) on the bottoms, and 19mm x 2.5 (CDS) on the tops (because I had some more than any other reason!)

Cheers

Alex

mine are all 1" (25mm) seamless, my cars's heavier than a locost though

25mm bottom and 19mm for the top

im gonna use 20x4 tube which i used for the crush tubes that i have lying around... incredibly heavy, impossible to work on, but i have lots of it which i dont use so i'll just use that. whats a couple of more kgs anyway!

I used 19mmx2mm seamless for upper and lower bones, 8K miles of bumper cornish lanes and still fine.