I attended a customers house to fix a reported leak from their shower waste. Turns out there was a split in the trap. Straight forward I thought and got a standard 90mm trap from the van. Turns out the hole in the shower base isn't big enough to fit the top section by the width of the thread on the upper section. When I measured the hole it was only 85-86mm wide. Has anyone else come across this before? The waste that was on there was unbranded and I haven't been able to find an equivalent online. I'll expand the hole if necessary but I thought all shower tray waste holes were standardised.