There are a few things that don't add up here,if you were getting 1st gear before your flywheel change,why did you change a g/box after fitting a new clutch etc,was your original fault getting no gears? Have had problems on these with after market solid flywheel kits, ie clutch clearance problems,if the grinding wasn't there before the prop shaft bearing was fitted then I would pinpoint that area as suspect,if you fitted a 2nd hand g/box then if you don't know any history about it then it may be your fault also,things seem to be getting worse the more parts you fit,
cdc, January 2016