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Pictures below by courtesy of Neil Rothschild show the dDB populated with 2n5088 / 2n5087 / 2n5484 / MJE243 / MJE253:
To get some kind of test board for trying different transistors, socket the transistor locations with SIP sockets. TO-92 transistors can pe plugged directly into the sockets. The legs of TO-220 are too large, solder SIP pins or SIP sockets to the transistor's legs.