firstly I said welded mount brackets are useless, You need big steel plates bolted to the sheetmetal of the car - welding makes metal brittle and eventually crack unless you have a mig welder and know how to weld smoothly.
Secondly adding spacers behind the front wheels would make the steer base offset from the rear, if you added spacers to make up for the lost offset of the wheel then you have wrong wheels.
Thirdly all those H22A, B16A, Toy 1MZ, Mitsi 4G63T, SR20DET swapped charades are money pits. They work for only ONE race and then require a complete overhaul of this velding etc etc from denter ustaad.
Lastly
Your original control arms mounts (mukkian as you say) were corroded and you had them rewelded. You will be quite shocked to hear that such a car is not even recommended to be driven any more AT ALL. the only workable repair is to spot weld an entire new panel that houses those control arm mounts - this is to be done on a chassis jig with optical alignment mirrors to ensure the body remains square.
If you want no nonsense raw racing car experience, get the denter to remove all rubber mounts, make a cradle for the engine and bolt it SOLIDLY to the car from the frame legs and the firewall. This will ensure all engine torque goes to the wheels, it also means you will have to make up some HD axle shafts to take the brutal shove and also make yourself agree to the insane booming vibration your car will have.
in precis to the above.
your car has spread and bowed - there is no stopping this and it will only get worse. That is why I always tell people to think 100 times before "swapping" anything - because you pay money to the denter on your own responsibility. when something breaks they charge you again because its a swapped car - not original design.
If daihatsu thought this car would be capable of handling that weight they would have provided such engines too, cars are built to the cheapest factor (specialy econo cars like yours) hence they are already at their last edge. You just pushed it over with a heavy engine, powerful torque and mismatched weight on corroded welded chassis frame.
I would suggest you drive it gently only.
