I think 88 degree is the standard. Few quid on ebay.

I may have my old housing in the shed - I replaced mine with an ally one. I'll have a look after tea,

"Y mae dafad ddu ym mhob praidd"
1972 4/4, 1981 MGBGT, 1984 FLHT1340, 1980 XLH1000, 1990 ZX10