tektronix 540 navram options firm 2.00 possible upgrade to higher levels

[Tektronix 540 (rotto)]

tektronix 540 navram options firm 2.00 possible upgrade to higher levels; I replaced the capacitors and navram and installed the vers. 2F_13, but I had errors; later I was able to reprogram the same files in the old navram and now I have only error related to port 232 which is not installed.
if anyone help me now i have the following problem even if i update the system date the next day i find that the date has not passed to the next day.
Also I'd like to upgrade its current capability to some superior features; if this is possible I have read several posts but obviously I would like some advice to proceed in the most correct way.
Also available to replace the cpu card with a higher-end one

[Tektronix 540 (rotto)]

I add the photos of this latest update after rewriting the files in the old navram errors have been removed; but I am left with this flaw in the update date

[Tektronix 540 (rotto)]

I am attaching photos for your help

[picburner]

Regarding the issue of keeping the date:

The TDS540 doesn't have an RTC, so it is normal for it to lose the day and time, U1107 is a 128Kx8 SRAM only.
Moreover this fact is specified in the user manual pag. 106 (chapter 3-44).

[Tektronix 540 (rotto)]

I have programmed a new navram and I have also removed option 13 so I have no more errors, but the date error remains. i think i could go deeper around the nav because there are jumpers that i might have to close like pc

[Tektronix 540 (rotto)]

then if this is not a step forward, I have to buy a 500 Mhz probe what checks can I do to understand that it works perfectly