IKZ TE Engine maintenance question

[FlashG]

Hi from the South Pacific I am trying to plan the maintenance of my wonderful 94 Hilux Surf 1KZ-KZN130W Due to Covid I need to keep it Now done 340,000 kms Done the head as many of us do at 242,000 Glow plug and injectors never touched As to the motor itself I have been told and believe a compression test is a big task and to use the voltage drop test as a way of testing compression Any thoughts on above please Seasons greetings

[Graham Hugh]

Also changed my head at 270.00 km. Changed glow plugs over said it cant be done . Just dont breenge. Went fine .Replaced injectors was told they are unusual for a vehicle. They are more suited to a commercial generator. When changing head dont waste money on new head bolts .originals are superb quality . No stretch or deterioration whatsoever