Will this 1" threaded fork fit my bike?

[Psyclist]

Here is the link -> http://www.ebay.co.uk/itm/RH-O-1-si...Cycling_Parts_Accessories&hash=item460d140437

My fork on my Mercian has a slight crack in it, so was going to buy this fork.

Does anybody know if it'll fit? And will it still work if I cut it down (i.e have the thread on the end)

Thanks.