I just read your message and wanted to respond. I do have some refferences so if you have a Bible it would be good to grab it.
Mt.22:62, Mk.15:42, Lk.23:54, Jn.19:14 make it very clear that Jesus Christ was crucified "on" the Day of Preperation. This day allowed the Pachal lamb to be sacrificed and prepared for the next day which of course was the beginning of the Feast of Unleavened Bread, which began with the Passover feast itself. This feast lasted for 7 days and began on the 15th. day if Nisan(would be our month of April) every year. The month of Nisan was considered the beginning of the Jewish sacred year. A Jewish day runs from sunset to sunset.
All four Gospels make it very clear that Jesus and the desciples ate the passover meal together and did this ahead of time in the beginning stages of Preperation Day itself in the very early evening. Mt26:20, Mk.14:17, Lk.22:14, Jn.12:1.
All four Gospels make it very clear that he was betrayed and arrested in the early evening of that same day, following the last supper and of course still in the early stages of Preperation Day Mt.26:47-56, Mk14:43-52, Lk.22:47-53, Jn.18:2-11.
All four Gospels make it very clear that he was on trial for most of the late night and morning hours of the first part of Preperation day, seeing many different accusers and some (Pilate) more than once Mt.26:57-67,27:1-26, Mk.14:53-65,15:1-15, Lk.22:54-71,23:1-26 Jn.18,19:1-15.
In John 19:14 he makes reference to the time being the "sixth hour" meaning it was 12:00 midnight and also clearly names it as part of Preperation Day, the day before passover.
In John 19:31 it is also made very clear that Jesus was hanging on the cross "on" Preperation day the day before the passover feast. The Jews were very afraid that Jesus would not die before the end of Preperation Day thus continuing to hang on the cross past sunset and therefore into the next day which was the beginning of passover and a special sabbath for that occasion. So they asked to break his legs to speed up the process. But of course he was already dead.
Mt27:62 also makes it very clear that Jesus was crucified "on" the Preperation Day, seeing that the Pharisees asked for a special gaurd the next day after to watch over the tomb so that his body would not be stolen.
As I stated earlier Prep Day was the day Jews sacrificed and prepared the Pachal lamb for the passover the next day. The hours to do this were from 12:00 noon to 3:00 pm. Prep Day and it was done at the temple. Whats amazing is Jesus Christ hung on the cross for those exact same hours, the Sacrificial Lamb for the sins of the world.
Clearly he was crucified before the Passover and verified by all four Gospels.