Ah! I see, in the UK for some reason brass plates weren't generally stolen until the final years of steam engines when some got stolen, but the names being unique made them rather obvious. Other brass plates were melted down in the world wars and replaced with base metal plates. 

Alex Schneider

Paul Doggett.     England 🏴󠁧󠁢󠁥󠁮󠁧󠁿 

I don't know whether the studs were bolts or rivets. I suppose that they might just have used self tapping screws but l have never heard of this. The plate is most unlikely to be threaded even if the bolt was, because the plate needs to be clamped tightly between the head of the fastener and the car side. In similar circumstances with cast iron or steel plates I first clean the plate with scrapers and wire brushes which might loosen the fasteners. High localized heat might loosen the fastener. If you are knocking the fastener. Support the plate well with the fastener over a hole that is slighter bigger diameter that the. Fastener. Hammer onto a stick or dowel. The fastener usually comes out. Years ago l collected over a 100 cast plates off British freigh cars. Some taken off the car side. If the plate is aluminium be careful using heat. If it is plastic just ignore every thing l've said. 

A brass plate would be an uneccessary expense, why anyone thinks it would only last a year l don't know. British steam locomotives had often had brass builders plates, also sometime nameplates and number plates, they lasted as long and longer than the locomotive. A genuine brass plate off a locomotive can be identified by the rust and paint deeply ingrained into the back where it was fastened to the locomotive. 

Alex Schneider