[mickm3for]

Hi the transistors are 2sc2099 in the 50w pa they contain beyllium oxide this is in the heat sinking within the transistor case do not put force or excess heat as this will cause the top to become adrift exposing the oxide this is toxic.
the col is at 12v Bace is a low bias voltage via a regulator this is Q2205. The driver is Q 2202
place an amp mtr in series with connection final 13.5 v this should show the standing current when on tx and increase with modulation
As to removing remove the 2 screws and carefully remove each of the 4 legs 1 at a time do not subject force to transistor body i find a thin blade helps to lift tab
when used with soldering iron.
the cut off tab is the c one op. is the b the other 2 the e