Tip: When determining a time limit, remember that players won't be as familiar with the level as you are. If you normally complete the level with around 100s left on the timer, others might run out of time on their first try.
The routine that updates the values of all the addresses used for the status bar ($0EF9-$0F2F).
$008E28 - Change this address to AD to disable the timer.
$008E2E - Timer speed (USE WITH $008D8B)
$008E5C - Time is Running Out SFX. Change from FF to 00 to stop the music from speeding up when time reaches 99.
$008E6B - [22 06 F6 00] Change to [EA EA EA EA] to not kill Mario when the timer reaches zero. The timer will count down normally and stop at zero, but Mario will not die
$008EDB - Change this and/or $008F09 from 20 12 90 to EA EA EA to disable writing the score to the status bar when playing as Mario and/or Luigi, respectively. Useful if you want to place another counter in place of the score using Smallhacker's Status Bar Editor. Note: This alone will NOT stop writing blank tiles if the first N tiles/bytes at $0F29-$0F2E contains the value #$00 (the "0" graphic). To prevent that, consider using this patch.
$008EE3 - Change to BRA  to write zeroes instead of blank tiles to Mario's score counter. Use with $008F11.
$008F11 - Change to BRA  to write zeroes instead of blank tiles to Luigi's score counter. Use with $008EE3.
$008F2C - How many coins you need to get an 1up (USE WITH $008F37)
$008F2F - [EE E4 18] Change to [EA EA EA] to not gain a life after collecting enough for one.
$008F37 - Number of coins to subtract from the counter when you gain enough for a 1up (Default: $64 (100). Change to  to create a coin wallet effect - use with $008F2F.
$008F41 - (Use with $008F45) Maximum life limit, minus one. Warning: Changing this to anything higher than 0x7E (127 lives) will remove the life limit entirely! Also, if you have more than
99 lives, the life counter will appear slightly glitched.
$008F45 - (Use with $008F41) Maximum life limit, minus one. Note that if you have more than 99 lives, the life counter will appear slightly glitched.
$008F62 - Number of bonus stars required to enter bonus game
$008F67 - [8D 25 14] Change to EA EA EA to disable entering bonus game when player has 100 bonus stars.
$008F6F - Amount of bonus stars that will be subtracted when 100 bonus stars are collected. Change to  to make 99 the maximum amount of bonus stars you can get - to create a bonus star wallet effect, use with $008F67.
$008F7E - Writes coins to status bar. Changing to [EA EA EA EA EA EA] will disable the coins from being written to the status bar.
$008F95 -  The X position of the small bonus star counter in the status bar.
$008FC5 - [20 79 90] Change to EA EA EA to disable the item GFX in the status bar
$008FCE - Length of "LUIGI" text (Status bar)
$008FE7 - [FC](blank tile) Tile used on the status bar when there's no Yoshi coin in that spot.
$008FED - [2E](coin tile) Tile used on the status bar when there is a Yoshi coin in that spot. Change to [FC](blank tile) to visually disable collected Yoshi Coins.