225 R26 thermostat housing on a PH1 225?

Hi all,

I've discovered this week that I've had a pretty major coolant leak, the source of the leak being from the rubber bung/cover on the thermostat housing as it had perished and split therefore leaving a hole for coolant to spill out. Having looked at a few other threads I've noticed that the design of the thermostat housing changed on the R26, so where my car has the rubber bung the R26 part has the hole welded over to stop coolant leaking out.

My question is, can I fit an R26 thermostat housing to my PH1 225? I'm assuming the bung on my thermostat housing was there to literally stop coolant coming out. The part number appears to be the same too (8200338668).

Any help/advice would be appreciated!